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Thyristor-based onload tap-changing AC voltage stabilizers are cheap and robust. They have replaced most mechanical tap-changers in low voltage applications from 300 VA to 300 kVA. Nevertheless, this replacement hardily applies to tap-changers associated to transformers feeding medium-voltage lines (typically 69 kV primary, 34.5 kV line, 10 MVA) which need(More)
Power insulated-gate bipolar transistor (IGBT) and other gate turnoff switches have allowed to analyze, in a previous paper, four new circuits for onload-tap-changing ac stabilizers that typically permit to make up to 7 or 45 (depending on the particular circuit solution) changes per half cycle of the mains voltage. This second and last paper considers the(More)
The rate of change in classic thyristor-based onload tap-changing ac stabilizers is limited to that of the load current zero crossing (once per half cycle) due to the natural turnoff method involved. The growth of the power rate of insulated-gate bipolar transistor and other gate turnoff switches allows exploring of stabilizers that are able to change taps(More)
The United Nations Atlas of the Oceans (http://www.oceansatlas.org) has been developed by various groups (UN and national agencies and NGOs) and individuals having an interest in the sustainability of oceans and coastal areas. Its objective is to contribute to sustainable development of the oceans and coastal areas and to the advancement of ocean science(More)
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